English

A Buchsbaum theory for tight closure

Commutative Algebra 2022-08-16 v2

Abstract

A Noetherian local ring (R,m)(R,\mathfrak{m}) is called Buchsbaum if the difference e(q,R)(R/q)e(\mathfrak{q}, R)-\ell(R/\mathfrak{q}), where q\mathfrak{q} is an ideal generated by a system of parameters, is a constant independent of q\mathfrak{q}. In this article, we study the tight closure analog of this condition. We prove that in an unmixed excellent local ring (R,m)(R,\mathfrak{m}) of prime characteristic p>0p>0 and dimension at least one, the difference e(q,R)(R/q)e(\mathfrak{q}, R)-\ell(R/\mathfrak{q}^*) is independent of q\mathfrak{q} if and only if the parameter test ideal τpar(R)\tau_{\text{par}}(R) contains m\mathfrak{m}. We also provide a characterization of this condition via derived category which is analogous to Schenzel's criterion for Buchsbaum rings.

Keywords

Cite

@article{arxiv.2108.02615,
  title  = {A Buchsbaum theory for tight closure},
  author = {Linquan Ma and Pham Hung Quy},
  journal= {arXiv preprint arXiv:2108.02615},
  year   = {2022}
}

Comments

20 pages, final version

R2 v1 2026-06-24T04:51:36.826Z